Ash disposal – mine fires – environment: an Indian dilemma

Abstract

The paper discusses the problems of ash disposal from coal combustion in two large coal-mining regions in India. Compared with the United States, India produces some three times the amount of coal ash per million metric tonnes of domestically produced coal, 95% of which is sluiced into gigantic slurry ponds located near urban areas and occupying vast amounts of premium land. The Jharia Coalfield produces some 30 million tonnes/year of ash and contains the world's largest complex of underground coal-mine fires, occupying an aggregate surface area of about 10 km2 above which the land surface is extremely degraded. Similarly, the Singrauli Coalfield suffers from the environmental effects of open-cast mining, spoil heaps and an enormous coal combustion ash disposal problem. Ash haulback is proposed as an efficient, cost-effective way of removing significant quantities of ash from the surface/pond disposal and placing it in open-cast and underground mines. In addition to contributing to the control of mine fires and subsidence, it is suggested that this would have numerous beneficial effects in terms of the reclamation of poor-quality/degraded land for sustainable, productive use and the reduction of harmful emissions and substances in populated areas.